This proposal describes a plan for a Preventive Oncology Academic Award and my personal development towards a multi-disciplinary approach to breast cancer prevention and control. Two projects are described, the first using data from the 1987 Texas Breast Cancer Screening Project, a state-wide mammography program, to validate or refine the risk model for breast cancer devised by Gail et al. (1990) that gives a numerical life-time breast cancer risk estimate. This validation follows-up a study of risk and use of the Gail model previously completed (Bondy et al.) which assigned risk scores to women who participated in the 1987 TBSP. During the award period, we will contact the 3,165 women identified as being at high risk to check the accuracy of their risk scores. We will mail a detailed risk factor questionnaire to gain additional information and identify women who have developed breast cancer since their participation in the TBSP. We will then conduct a nested case-control study with the newly detected breast cancer cases to validate the Gail model, or devise a refinement of it and calculate a new breast cancer risk determination model. If we can ascertain we have accurately determined degrees of risk or what factors are needed to determine risk, we can improve the general effectiveness of screening programs in identifying high risk individuals. The second project, a primary prevention effort, is a case-control study of breast cancer risk factors in Hispanic women. The study incorporates epidemiologic risk factor data with molecular genetic marker data to provide a better understanding of the etiology of breast cancer in Hispanic women. The study aims to identify modifiable risk factors for breast cancer where alteration would lead to a reduction in breast cancer morbidity and mortality. These two projects, though focusing on genetics, have broader applications and would lead to investigations of environmental and genetic interactions. This award will advance comparative ethnic research and the assessment of breast cancer risk in high risk populations. Research enabled by the award will broaden my understanding of the interactions of molecular genetic markers and epidemiologic risk factors related to the etiology of breast cancer and benefit the field of preventive oncology.